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*
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
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package org.graalvm.compiler.replacements.nodes.arithmetic;
import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_4;
import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_2;
import org.graalvm.compiler.core.common.type.IntegerStamp;
import org.graalvm.compiler.graph.NodeClass;
import org.graalvm.compiler.graph.spi.CanonicalizerTool;
import org.graalvm.compiler.nodeinfo.NodeInfo;
import org.graalvm.compiler.nodes.AbstractBeginNode;
import org.graalvm.compiler.nodes.ConstantNode;
import org.graalvm.compiler.nodes.ValueNode;
import org.graalvm.compiler.nodes.calc.MulNode;
import org.graalvm.compiler.nodes.spi.LoweringTool;
import jdk.vm.ci.meta.JavaConstant;
import jdk.vm.ci.meta.JavaKind;
/**
* Node representing an exact integer multiplication that will throw an {@link ArithmeticException}
* in case the addition would overflow the 32 bit range.
*/
@NodeInfo(cycles = CYCLES_4, cyclesRationale = "mul+cmp", size = SIZE_2)
public final class IntegerMulExactNode extends MulNode implements IntegerExactArithmeticNode {
public static final NodeClass<IntegerMulExactNode> TYPE = NodeClass.create(IntegerMulExactNode.class);
public IntegerMulExactNode(ValueNode x, ValueNode y) {
super(TYPE, x, y);
setStamp(x.stamp().unrestricted());
assert x.stamp().isCompatible(y.stamp()) && x.stamp() instanceof IntegerStamp;
}
@Override
public boolean inferStamp() {
/*
* Note: it is not allowed to use the foldStamp method of the regular mul node as we do not
* know the result stamp of this node if we do not know whether we may deopt. If we know we
* can never overflow we will replace this node with its non overflow checking counterpart
* anyway.
*/
return false;
}
@Override
public ValueNode canonical(CanonicalizerTool tool, ValueNode forX, ValueNode forY) {
if (forX.isConstant() && !forY.isConstant()) {
return new IntegerMulExactNode(forY, forX).canonical(tool);
}
if (forX.isConstant()) {
return canonicalXconstant(forX, forY);
} else if (forY.isConstant()) {
long c = forY.asJavaConstant().asLong();
if (c == 1) {
return forX;
}
if (c == 0) {
return ConstantNode.forIntegerStamp(stamp(), 0);
}
}
if (!IntegerStamp.multiplicationCanOverflow((IntegerStamp) x.stamp(), (IntegerStamp) y.stamp())) {
return new MulNode(x, y).canonical(tool);
}
return this;
}
private ValueNode canonicalXconstant(ValueNode forX, ValueNode forY) {
JavaConstant xConst = forX.asJavaConstant();
JavaConstant yConst = forY.asJavaConstant();
assert xConst.getJavaKind() == yConst.getJavaKind();
try {
if (xConst.getJavaKind() == JavaKind.Int) {
return ConstantNode.forInt(Math.multiplyExact(xConst.asInt(), yConst.asInt()));
} else {
assert xConst.getJavaKind() == JavaKind.Long;
return ConstantNode.forLong(Math.multiplyExact(xConst.asLong(), yConst.asLong()));
}
} catch (ArithmeticException ex) {
// The operation will result in an overflow exception, so do not canonicalize.
}
return this;
}
@Override
public IntegerExactArithmeticSplitNode createSplit(AbstractBeginNode next, AbstractBeginNode deopt) {
return graph().add(new IntegerMulExactSplitNode(stamp(), getX(), getY(), next, deopt));
}
@Override
public void lower(LoweringTool tool) {
IntegerExactArithmeticSplitNode.lower(tool, this);
}
}